| 摘要 |
The invention relates to a method for monitoring play between a drive device screw 9 and a drive device nut 8 intended for manoeuvring a control rod which is inserted from below into the core of a nuclear reactor. According to the invention, the drive device is provided with a sensor 17, 18 which indicates turns and parts of a turn by which the drive device screw 9 is rotated during manoeuvring. An unworn drive device nut 8 is advanced to a given defined indication position, preferably its upper mechanical stop 22, the drive device screw 9 also being stopped in a first turn-count position which is read off via the sensor 17, 18. After a certain period of operation, the same procedure is repeated, that is to say the drive device nut 8 is again moved to the same indication position, preferably the upper mechanical stop 22, the drive device screw 9 also being stopped and its second turn-count position being read off. The difference in turns and/or parts of a turn between said turn-count positions is then determined. This difference corresponds to the nut wear which has arisen during the period of time which has elapsed (Fig. 4). <IMAGE> |
